Lamps that are provided for attachment to a ceiling of a room that is to be illuminated and which are designed to project light substantially downward are normally referred to as “downlights.” These are normally recessed lamps, which are designed such that they can be mounted in the mounting hole of a suspended ceiling element, e.g. a sheetrock ceiling.
Recessed ceiling lamps of this this type, in the form of downlights, are known in different configurations. Thus, lamps are known that have a circular light emission surface, and are then normally secured to the ceiling via a circular installation or mounting frame. In contrast, the present invention relates to downlights having an angular design, in particular square or rectangular. In this case, the mounting frame can be designed as a mount for a single light fixture as well as for numerous light fixtures that are to be disposed adjacently to one another.
The use of the mounting frame specified above serves to simplify the installation of the downlight, as well as later repair or maintenance measures. Only the mounting frame is permanently joined to the ceiling construction, e.g. via a screw connection or a special clamping construction, and optionally plastered over for optical reasons. The actual lamp, on the other hand, including the light fixture having the luminaire head located thereon, is designed such that it can be attached to the mounting frame in a releasable manner. The actual installation of the downlight can thus first occur when all of the other preparations, in particular the attachment and plastering of the mounting frame have been completed. Furthermore, it is not necessary to fully remove all of the components in order to exchange the luminaire head, or the light source of the downlight, but rather, it is sufficient to release only the light fixture from the mounting frame, wherein the mounting frame remains permanently in the ceiling. For this it is necessary, as a matter of course, to enable a simple, reversible attachment of the light fixture to the mounting frame, while at the same time the connection is designed such that the light fixture having the luminaire head located thereon is reliably retained on the mounting frame and cannot release itself therefrom.
Different solutions for this are known from the prior art. A first known variation provides, for example, that the light fixture is placed in the mounting frame such that it is slightly twisted, and is then locked in place therein. A locking in place via a special spring mechanism or a screwing of the light fixture to the mounting frame is also known. None of these various variations, however, have proven to be optimal, because, e.g., with the first variation, in which a twisted insertion and subsequent locking in place is provided, the light fixture together with the recessed lamp cannot exceed the width of the frame with regard to its height. Furthermore, for this type of installation, an extremely stable light fixture is required, and an additional securing, e.g. in the form of a snapping or locking in place, is required, in order to eliminate the risk of the light fixture falling out of the mounting frame when it is moved. A removal of the light fixture in this case necessarily requires a lot of effort and strength, wherein the same also applies with the use of corresponding spring mechanisms, because in this case, the springs must be designed such that they are strong enough to retain the light fixture with the additional luminaire head. Furthermore, in this case a relatively large gap is necessary in order to enable removal, potentially using tools. This leads in turn to the possibility that unattractive gaps may result with so-called channel solutions, in which numerous light fixtures are disposed adjacently to one another in a mounting frame.